There's a proper way to approach the food, and the Archuletas want you to know about it - but in a fun way. If the place wasn't so casual - dark walls and uncomfortable straight-back wooden chairs and benches - you might mistake it for a similar attitude prevalent at French restaurants in the 1970s rather than a sushi bar in the Mission.

Archuleta has a two-decade track record of perfecting his skills. He started his sushi sojourn at Paradise Sushi in Capitola before moving to San Francisco, where he worked in Japantown and then went on to Ace Wasabi and Tokyo Go Go.

Bigger space

He founded Ichi in 2006 and added the sushi bar in 2010. Earlier this year, he closed the original Bernal Heights location to open this larger space a few blocks away on Mission Street.

The new location encompasses a sushi bar and 30-seat restaurant and another open room behind, called the Ni Bar, that accommodates 40. In the sushi area, diners have access to the entire menu; the lounge menu is limited to sashimi and a dozen or so other dishes.

The nigiri starts at $5 for such things as shrimp and goes up to $9 for specials such as Japanese golden eye snapper. Rolls are in the $3.50-$7 range.

On two nights, we hopscotched around the menu, getting suggestions from the waiter along the way. On another visit, we asked the chef to prepare an omakase menu to show off his cutting, searing, wrapping and condiment-dabbing techniques.

After that meal, which featured dishes from the regular menu, we decided that letting the chef orchestrate the experience was the best way to go. The menu is mostly nigiri, progressing from lighter to heavier preparations, with a few cold and hot dishes in between to round out the dinner. Diners determine the number of courses.

We kept eating and eating because we were so intrigued by what Archuleta was doing; the fish and the order in which it was served seemed more coherent than when we ordered on our own. Before we knew it, we had spent about $90 a person for food. For quality sushi, that's not bad.

Our meal started with two oysters apiece, arranged like a starburst on a mound of crushed ice. Those were quickly followed by four kinds of sushi: tuna with a swipe of tare underneath; Japanese halfbeak with daikon chile dabbed on top; kampachi with yuzu and Meyer lemon zest; and barracuda wrapped in kelp for three days and then quickly seared before it made its way to the rice pad.

Fine chips

In between, Archuleta sent out a small bowl of barely cooked asparagus in a thick black sesame dressing topped with bonito flakes; and a little pile of fried fish bones designed to be eaten like potato chips. They were better than any chip I've had - a bit briny, but mostly thick and crunchy.

Then came another round of nigiri including a braid of tiny Japanese whiting fillets; and Japanese sea bass so thinly sliced, you could see the shisho leaf wrapped around the pad of rice below.

The only sashimi was Japanese skipjack covered with delicate sprouts, fried garlic bits and chile daikon; it was like walking through a forest and finding a treasure of bold and delicate flavors. Another round of nigiri followed and then a hot dish of Asari clams in a rich pork both, a combination that shows the kitchen is equally skilled with hot food.

After conferring with our waiter, we decided we could handle another round of what would be the more intense fish preparations. We each got our own platter that included rich tuna belly, grilled unagi, a vivid Japanese uni and a milder local sea urchin. The last bite was a chef's creation of tamago, an omelet made with Japanese chicken eggs.

Archuleta has an arsenal of house-made condiments that he uses to balance the acid, salt and spice. He keeps several kinds of salt at his fingertips and also utilizes several types of citrus and three kinds of ponzu, all made in-house.

Every bite is self-contained and seasoned to bring out the best in the fish - which is why you won't find a pitcher of soy sauce on the table.

On the two visits where we ordered on our own, one of the most vivid dishes was four thick slices of lightly seared albacore tuna tataki ($12.95). They were drizzled with a shallot shisho vinaigrette and topped with garlic chips that looked like tiny white flowers.

Hot dishes include yuzu fried chicken wings ($9.50) with a light, crisp coating that holds in the scalding juices. It's one of the best versions of fried chicken wings I've tasted.

Most places have one or two fish collars; Ichi has eight, including Canadian albacore tuna ($14), ocean trout ($10) and golden eye snapper ($12), all salt-broiled. Each has a distinctive flavor, but in all cases the meat is the juiciest and most intensely flavored morsel on the fish.

Another distinctive hot preparation is a delicately crusted chunk of ocean trout ($9.75) surrounded by a light dashi broth that accentuates the trout's fresh notes.

About the only disappointments were the skewers of chicken thighs with tare ($3.50), pork shoulder with miso ($3.50) and the flank steak with yuzu ponzu ($3.75). They weren't bad, but not as delicately conceived as the other offerings.

The Archuletas have created a restaurant that has found even more devotees in its new location. From the minute you walk in the door and the staff shouts the traditional Japanese greeting to the carefully executed dishes coming out of the kitchen, you know you'll be in good hands.

The wine list

Given the variety of the fish and the complexity of the preparations - and the fact that there's a separate bar in back - the beverage list could be a little more expansive.

The 11 sakes, all offered by the glass or bottle, cover all the bases but don't venture out of the ordinary. Selections include Miyasaka Yawaraka Junmai ($9/$40), Hakkaisan Junmai Ginjo ($15/$67) and Hoyo Kura no Hana ($16/40). In addition, the restaurant features a half-dozen shochu selections such as Kinjo Shiro ($9), made from rice; Tomino Hozan ($11), from sweet potato; and Kakushigura ($9), made from barley.

In wine, Ichi serves just one sparkling - Casas Del Mar Blanc de Blancs ($9/$35) - along with four whites, including the 2012 Tangent Sauvignon Blanc ($10/$45); a rosé; and three reds such as the 2011 Andis Primitivo ($10/$45) that will be unfamiliar to many diners.

Five beers include Almanac's Ichibier Yuzu Shiso Ale ($6), three from Asia and the Mission Hefeweizen Bavarian Style Wheat ($6).

Prices are based on main courses. When entrees fall between these categories, the prices of appetizers help determine the dollar ratings. Chronicle critics make every attempt to remain anonymous. All meals are paid for by The Chronicle. Star ratings are based on a minimum of three visits. Ratings are updated continually based on at least one revisit.